One wrong document can delay your shipment, cost you thousands, or even lead to customs rejection. Could the missing piece be a Shipper’s Letter of Instruction (SLI)? This crucial document plays a vital role in international trade, outlining a shipper’s instructions to the freight forwarder.
For Australian businesses involved in global trade, understanding SLIs is essential. Whether exporting goods by sea or air, a correctly completed SLI helps ensure compliance, prevent costly delays, and streamline the shipping process. In this article, we will explore what an SLI is, why it matters, when it is required, and how to complete it correctly to avoid common mistakes.

What is a Shipper's Letter of Instruction (SLI)?
Firstly, let’s define exactly what an SLI is. Essentially, a Shipper’s Letter of Instruction (SLI) is a formal document that provides a detailed set of instructions from the shipper to their appointed freight forwarder. Specifically, this document acts as a detailed guide, ensuring the freight forwarder understands and executes the shipper’s precise requirements for the shipment. In other words, it’s the shipper’s way of saying, “Here’s what I need, and here’s how I need it done.”
Furthermore, to fully grasp the importance of an SLI, it’s crucial to understand its key components.
Key Components of an SLI
- Shipper and Consignee Details: Indeed, this includes accurate names, addresses, and contact information for both the sender and the receiver.
- Goods Description: Moreover, a detailed description of the goods being shipped, including quantity, type, and value.
- Shipping Instructions: Additionally, the preferred shipping method (sea, air, road), routing, and any specific requirements.
- Special Handling Requirements: Likewise, any unique instructions for handling the goods, especially if they are fragile, hazardous, or require specific temperature control.
- Insurance Information: Also, details about insurance coverage for the shipment.
- Customs Information: Then, any information relevant to customs clearance, such as HS codes and export documentation.
To illustrate this point, imagine a simplified SLI as a checklist, ensuring all bases are covered.
Ultimately, the SLI serves as a vital communication tool, bridging the gap between the shipper and the freight forwarder. In fact, it ensures clarity and minimises the risk of misunderstandings that could lead to costly errors and delays. However, it’s important to note that SLI documents can vary depending on the mode of transport. For instance, there might be specific SLI templates for seafreight versus airfreight. Therefore, your freight forwarder will typically provide the correct template, tailored to your specific shipping needs.
What is the Purpose of an SLI?
The primary purpose of an SLI is to provide clear shipping instructions and facilitate international trade. It serves several important functions:
1. Providing Clear Instructions to the Freight Forwarder
Firstly, the primary purpose of an SLI is to provide clear and simple instructions to the freight forwarder. Essentially, this document acts as a roadmap, guiding the freight forwarder through the entire shipping process, from pickup to delivery. Therefore, by detailing every aspect of the shipment, the SLI minimises the chance of errors and ensures the goods are handled according to the shipper’s specific requirements.
2. Ensuring Compliance
Secondly, the SLI plays a vital role in ensuring compliance with Australian export regulations. Indeed, international trade is governed by a complex web of rules and regulations, and the SLI helps shippers navigate these complexities, specifically within the Australian framework. Specifically, it ensures that all necessary information is provided to comply with Australian customs and other regulatory requirements. In particular, the SLI is essential for compliance with specific regulations, such as the Australian Customs Act 1901 and the Export Control Act 2020. These regulations mandate that exporters provide detailed information on the goods being exported, including the Australian Harmonized System (AHS) code, country of origin, and value of the goods. As a result, the SLI ensures that this information is accurately recorded and provided to the freight forwarder, ensuring compliance with Australian export regulations. In fact, this is especially vital for Australian businesses, as it helps them avoid penalties, ensures their goods move through the system without unnecessary delays, and maintains their reputation as reliable international traders.
3. Preventing Shipping Errors
Thirdly, the Shippers Letter of Instruction helps stop mistakes and misunderstandings. For example, if you write down exactly how to handle your goods and where to deliver them, everyone knows what to do. As a result, things run much smoother, and your business saves time and money.
4. Customs Clearance Support
Moreover, Shippers Letter of Instruction facilitates accurate documentation for customs clearance. Specifically, customs authorities rely on accurate and complete documentation to process shipments efficiently. Therefore, the SLI, along with other shipping documents, provides the necessary information to ensure smooth customs clearance, minimising delays and potential hold-ups.
5.The Role of the Shipper and Logistics Provider
Finally, it’s important to remember that the SLI is a team effort. On one side, the shipper must provide correct and complete information. On the other side, the freight forwarder must follow those instructions. So, good communication between both sides is key to a successful shipment.
When is a Shipper’s Letter of Instruction Required?
1. Sending Goods Overseas: International Shipments
Generally, if you’re shipping goods outside of Australia, you’ll need an SLI. Essentially, it’s a standard requirement for international shipments. Therefore, if your business involves exporting to any country, be prepared to provide an SLI to your logistics provider.
2. Special Shipping Situations
Furthermore, there are specific shipping situations where a Letter of Instruction becomes absolutely essential. For instance, when shipping via air freight or sea freight, the SLI is crucial for detailing specific handling and routing instructions. Similarly, if you’re dealing with complex shipments involving multiple destinations or specialised handling, the SLI ensures everyone is on the same page. Moreover, if your goods are classified as hazardous materials, an SLI is mandatory, alongside other required documentation, to ensure safe and compliant transport. Also, if you have any goods that require temperature control, or are very fragile, the SLI will allow you to give specific instructions.
3. When Your Freight Forwarder Asks For It
Additionally, freight forwarders often require an SLI as part of their standard operating procedures. In fact, it’s a common document they use to manage and process shipments efficiently. Thus, even if you’re unsure whether it’s strictly required, be prepared to provide a Letter if your freight forwarder requests it. Basically, it’s a good practice to comply with their requests to ensure a smooth shipping process.
4. Australian Customs Might Ask For It
Moreover, Australian customs may require an SLI in certain situations, especially when dealing with specific types of goods or complex shipments. Specifically, while not always explicitly stated, providing a well-prepared SLI can help streamline the customs clearance process. Therefore, having an SLI ready can prevent potential delays and ensure compliance with Australian customs regulations.
5. Working With a Third-Party Logistics Provider (3PL)
Finally, if you’re using a third-party logistics provider (3PL) to manage your shipments, they will almost certainly require an SLI. Essentially, a 3PL acts as an intermediary, managing your shipping needs.
Consequently, they need clear instructions to handle your goods effectively, and the Shipper Letter provides that essential communication tool.

How to Fill Out a Shipper’s Letter of Instruction?
Firstly, completing an SLI accurately is crucial to ensure a smooth shipping process. Therefore, follow these steps carefully to avoid errors and delays.
1. Shipper and Consignee Details
Essentially, this section requires accurate and complete information for both the exporting company (shipper) and the receiving business (consignee). Specifically, include:
- Full company names and legal addresses.
- Contact names, telephone numbers, and email addresses.
- Australian Business Number (ABN) or equivalent, if applicable.
Indeed, double-check all details to avoid delivery issues or customs complications.
2. Notify Party
Furthermore, the ‘Notify Party’ section is used to specify an additional contact person or company at the destination. For example, if your consignee works with a specific customs broker or freight forwarder in the destination country, include their details here. Otherwise, the shipment will be handled by your freight forwarder’s partner, which might cause delays. Therefore, filling this out correctly can streamline the arrival process.
3. Departure and Destination
Additionally, clearly state the port or airport of departure in Australia and the final destination. Usually, your freight forwarder will provide these details in their quote. However, if you have specific routing preferences, communicate them clearly. Essentially, this ensures your shipment follows the desired path.
4. Hazardous Cargo
Moreover, if your shipment contains hazardous materials, this section is critical. In fact, hazardous cargo requires a Material Safety Data Sheet (MSDS). Specifically:
- Clearly indicate that the shipment contains hazardous materials.
- Provide a complete MSDS with all necessary safety information.
- Be aware of and comply with all relevant Australian and international regulations for hazardous goods transport.
In particular, Australian businesses must comply with strict regulations, and errors can lead to serious penalties.
5. Special Instructions
Likewise, use the ‘Special Instructions’ section to detail any specific handling requirements. For instance, if your cargo is non-stackable, fragile, or requires temperature control, clearly state these needs. Essentially, this prevents damage and ensures proper handling.
6. Product Descriptions, Weight, and Measurements
Furthermore, provide detailed product descriptions, including quantity, type, and value. Also, accurately detail the weight and measurements of your goods. Specifically:
- Use clear and precise descriptions.
- Double-check weight and measurements to avoid additional charges.
- For seafreight, understand Verified Gross Mass (VGM):
- VGM Method 1: Weigh the entire container and its contents.
- VGM Method 2: Calculate the weight of the goods and packaging.
Therefore, accuracy here is vital to avoid delays and extra costs.
7. Charges Payable By
Then, clearly indicate who is responsible for paying shipping charges. To do this, refer to the Incoterms agreed upon with your buyer. (If available, insert link to your Incoterms guide). Additionally, this section is where you can specify if you require insurance for the shipment. Essentially, this protects your goods during transit.
8. Commercial Value
Moreover, state the commercial value of the goods, which is the selling or buying price, not the final retail price. Specifically, include the total value and the currency used. In fact, accurate valuation is essential for customs and insurance purposes.
9. Destination Requirements
Also, use this section to provide any specific instructions for the freight forwarder at the destination. For example, ‘Please provide a Proof of Delivery (POD) once delivered.’ Essentially, this ensures all your needs are met.
10. Signature & Date
Finally, sign and date the SLI. Basically, this confirms that you authorise the freight forwarder to proceed with the shipment based on your instructions.
Australian Specific Requirements:
- AHS Codes. Firstly, Australian businesses must use the correct Australian Harmonized System (AHS) codes for their goods. Incorrect codes can lead to customs delays and penalties.
- Export Declarations. Secondly, ensure you comply with all Australian export declaration requirements.
Digital vs. Paper SLIs:
Currently, many freight forwarders offer digital Shipper’s Letter of Instruction options, which can streamline the process. Thus, electronic signatures are also becoming more common. However, always ensure that digital documents comply with Australian legal requirements.

Common Mistakes to Avoid When Completing an SLI
Undoubtedly, even small errors in an Shipper’s Letter of Instruction can lead to significant problems. Therefore, Australian businesses must pay close attention to detail to avoid these common mistakes.
1. Incomplete or Incorrect Details
Firstly, incomplete or incorrect details are a major cause of shipment delays. Specifically, if the shipper or consignee information is wrong, or if product descriptions are vague, customs authorities and freight forwarders will struggle to process the shipment. Consequently, this can lead to:
- Delays in customs clearance.
- Shipments being held up in transit.
- Additional costs for corrections and storage.
- Missed deadlines and potential loss of business.
Essentially, every field in the SLI is important. Thus, double-check all information before submission.
2. Mismatched Documentation
Furthermore, mismatched documentation is another common issue. In other words, if the information in the SLI doesn’t match the details in the commercial invoice, packing list, or bill of lading, it raises red flags. Specifically, customs authorities will question the discrepancies, leading to inspections and delays. Therefore, ensure consistency across all shipping documents. Indeed, this protects you from delays and fines.
3. Ignoring Special Handling Instructions
Additionally, ignoring special handling instructions can lead to significant risks. For example, if your goods are fragile or require specific temperature control, and you fail to mention it in the SLI, they could be damaged during transit. Moreover, this miscommunication can lead to disputes and liability issues. Consequently, always provide clear and detailed special handling instructions.
4. Missing Exporter Authorisation
Finally, missing exporter authorisation, meaning the absence of a required signature, can invalidate the SLI. Basically, the signature confirms that you, as the exporter, authorise the shipment based on the provided instructions. Therefore, it has legal implications. In fact, without a signature, the freight forwarder may refuse to process the shipment, or customs may reject it. Thus, ensure that the SLI is signed and dated before submission.
Conclusion
Providing a properly completed Shipper’s Letter of Instruction is essential for ensuring smooth international shipments. A well-prepared SLI minimizes errors, prevents costly delays, and ensures compliance with Australian and international regulations.
By working with GenFreight, businesses can simplify the shipping process and avoid common documentation mistakes. Our team ensures that every SLI is accurate, complete, and compliant with all relevant requirements.
If you have any questions or need assistance, feel free to contact GenFreight for expert guidance and support.
Disclaimer
The information provided in this article is for general informational purposes only and is not intended to be a substitute for professional advice. GenFreight assumes no responsibility or liability for any errors or inaccuracies in the content of this article. Readers are advised to consult with a qualified professional before making any decisions or taking any actions based on the information provided in this article.